The present invention relates to a fluorescent lamp having a fluorescent tube and a lighting circuit board therefor.
In a conventional fluorescent lamp, for example, a bulb-shaped fluorescent lamp, examples of a method for connecting a lead wire of a fluorescent tube to a lighting circuit board include, for example, a lapping connection. In the lapping connection, as described in Publication of Japanese Patent Application No. Hei 10-275592 A, lapping pins 28, each having a square cross section, are provided on a lighting circuit board as connecting terminals and then lead wires 35 of a fluorescent tube are wound around the lapping pins 28 several times, thereby connecting the lead wires of the fluorescent tube and the lighting circuit board. In another conventional connecting method, Y-shaped connecting terminals are provided on a lighting circuit board and lead wires are inserted into the Y-shaped connecting terminals, thereby connecting the lead wires to the connecting terminals by caulking.
However, in such conventional bulb-formed fluorescent lamps, when the lead wires of the fluorescent tube are connected to the lighting circuit, the directions in which the lead wires extend are not the same. Therefore, it was extremely difficult to automate the connection by using a machine. Even when the connection is automated, faults are frequently found in that the lead wires cannot properly be connected to the terminals of the lighting circuit.
Furthermore, the lapping connection takes a long time since each lead wire is wound around each square pin five or six times. Therefore, the assembly operation efficiency is significantly impaired. On the other hand, the caulking connection by using the Y-shaped connecting terminals results in poor contacting due to vibration during transportation of the product even if the caulking is only slightly weak. Therefore, the reliability is not sufficient. Another problem is that the connecting terminal itself is expensive.
It is an object of the present invention to solve the problems of the prior art. That is, the object of the present invention is to provide a fluorescent lamp in which connecting terminals of a lighting circuit board and lead wires of a fluorescent tube easily can be connected and which is excellent in assembly operation efficiency, cheap and capable of achieving a highly reliable connection.
In order to achieve the above-mentioned object, a fluorescent lamp of the present invention includes a fluorescent tube, a holder holding the fluorescent tube, a lighting circuit board provided with a lighting circuit for lighting the fluorescent tube, and a case connected to the holder and housing the lighting circuit board. At the end portion of the lighting circuit board, cut-outs are formed, which widen toward an outer side of the lighting circuit board. In the vicinity of the inner narrow portion of each cut-out, the connecting terminal connected to the lighting circuit is provided. Each lead wire of the fluorescent tube is connected to the connecting terminal.
According to this configuration, since the lead wires of the fluorescent tube easily can be led to the connecting terminals of the lighting circuit board, it is possible to automate the connection between the lead wires and the connecting terminals. Thus, assembly operation efficiency and productivity can be improved.
In the above-mentioned configuration, the cut-out is V-shaped or Y-shaped. Thus, the lead wires of the fluorescent tube are easily led to the connecting terminals provided on the lighting circuit board, so that the position of the lead wire can easily be matched with the position of the connecting terminal.
Furthermore, in the above-mentioned configuration, cut-outs, which widen as the distance from the fluorescent tube increases and which are V-shaped or Y-shaped, are provided on a side wall placed on the holder opposite to the fluorescent tube and that the broad portion of the cut-outs of the holder and the broad portion of the cut-outs of the lighting circuit board are arranged facing each other.
According to this configuration, when the fluorescent tube is attached to the holder, the wires can be held by the side wall after they are bent toward the outer side of the holder. Therefore, after the fluorescent tube is attached to the holder, when the lighting circuit board is attached to the holder, the lead wires of the fluorescent tube are not obstructing to the attachment of the lighting circuit board. Furthermore, since the broad portion of the cut-outs of the lighting circuit board and the broad portions of the cut-outs of the side wall placed on the holder are facing each other, by bending the lead wires, which were bent toward the outer side of the holder, toward the side of the lighting circuit board, the lead wires easily can be led to the connecting terminals of the lighting circuit board. Consequently, the position of the lead wires easily can be matched with the position of the connecting terminals.
Furthermore, in the above-mentioned configuration, the lead wires of the fluorescent tube are connected to the connecting terminals of the lighting circuit board by welding. Thus, a strong connection between the lead wires of the fluorescent tube and the connecting terminals of the lighting circuit board can be realized, the reliability of the connecting portion is improved and the connection excellent in assembly operation efficiency can be realized.
Furthermore, the connecting terminal of the lighting circuit board may be a jumper lead wire. Thus, the position of the lead wires of the fluorescent tube can be matched with the position of the connecting terminals of the lighting circuit board more easily, and mass production can be realized o more easily and further cheaply.